A method of the aforementioned type is known from the article "SYNTHESIS OF OPTIMIZED ADAPTIVE DIGITAL FILTERS FOR SYSTEM IDENTIFICATION AND VIBRATION CONTROL" (J. Melcher, International Forum on Aeroelasticity and Structural Dynamics 1991, Eurogress Center Aachen, FRG). To identify the dynamic system, not only the system itself but also an electronic model of the system is excited using the signal `f`. The difference `e` between the system response and the model response is a measure of the matching of the system and the model. When adapting the model parameters to the system, the difference `e` is reduced to zero or is at least minimized. The above article is concerned exclusively with a method for the identification of a dynamic system with a single degree of freedom, whereby an acceleration is received as the system response. For this, the electronic model is given, besides signal flow `I`, an auxiliary signal flow with a parameter which is to be adapted further. Among the given conditions it is explained that the method described for on-line identification of the single degree of freedom for the system under observation is reliably suitable. In this context, the electronic model is designated as a digital filter. The fact that real dynamic systems almost always exhibit several degrees of freedom is regarded as a major disadvantage of the known system. The above article does not provide any help for their identification.
With another known method for the identification of dynamic characteristic quantities in a linear dynamic system, linear differential equations are used as a model for the system. This is encumbered with the major disadvantage that the method cannot be performed on-line. The time required for evaluating the system response is usually so long that, for example, a systematic and controlled influencing of the dynamic characteristic quantities through modifications to the system is not possible. After every modification to the system, dam must be recorded which then has to be evaluated in a separate step before the effects of the modification are defined. On the other hand, these known methods have the advantage that they are also suitable for the identification of dynamic systems with several degrees of freedom. However, the amount of work necessary to execute the method increases superproportional to the number of degrees of freedom due to their cross-linking.